Abstract: A non-invasive system for measuring the concentration of an analyte in an absorbing matrix is described. The system directs a beam of radiation at the matrix. The beam consists of a series of successive alternate pulses of electro-magnetic radiation, one of which is highly absorbed by the analyte and the other of which is non-absorbed. The transmitted or reflected beam is optically detected and an electrical signal proportional to beam intensity is used to adjust the beam intensity and as a measure of analyte concentration.

Abstract: A method and apparatus for non-invasively testing analytical substances in turbid matrices i.e. body fluids and tissues. In this method a sample is irradiated with a beam of electromagnetic energy at two alternating wavelenths, .lambda..sub.1 and .lambda..sub.2, at which the absorption by the background is the same but at one of which the radiation is absorbed by the analyte and at the other it is not. The apparatus comprises means which enable to control the input energy at .lambda..sub.1 and .lambda..sub.2 so that at the output from the sample the electric signals issuing after detection cancel in the absence of the analyte in the sample. When analyte is present cancellation no longer occurs and a signal proportional to the analyte concentration in the sample is produced. The apparatus is also designed for shifting the response back to zero when a calibrating known concentration of analyte is used as standard, thus providing a controllable zeroing base line.

Abstract: The invention concerns an immunological assay system, wherein the inner face of the cuvettes is used as the solid phase. The equipment includes a displaceable carriage (8) for the cuvette set as well as, above the carriage, a dosage head (9), to which the liquid dosimeter (11) and the measurement device (19) are attached. All the operations take place automatically.

Abstract: The invention concerns an immunological assay system, wherein the inner face of the cuvettes is used as the solid phase. The equipment includes a displaceable carriage (8) for the cuvette set as well as, above the carriage, a dosage head (9), to which the liquid dosimeter (11) and the measurement device (19) are attached. All the operations take place automatically.

Abstract: Immunological fluorometric assay method, wherein an antigen (1) attached to magnetic particles (3) reacts in a liquid with an antibody (2) present in the sample and with an antibody (4) marked with a fluorescent substance. After the reaction, the particles are pulled by means of a magnetic field through a second (6) liquid layer onto the bottom of the measurement vessel, whereupon the particles are excited, and emitted radiation is collected through the wall of the vessel.

Abstract: Method for carrying out immunoassays, in which method an antibody (or antigen) labeled with a tracer so as to be fluorescent is attached onto an antigen (or antibody, respectively) present at the inside wall of the measurement vessel, a liquid denser than the sample is added to the measurement vessel, which said denser liquid displaces the liquid from underneath, and both the excitation radiation is passed into the sample and the fluorescent radiation is collected to the detector through the wall or the bottom of the measurement vessel.

Abstract: Fluorometric immunological assay method in which an antigen is attached onto magnetic particles, which are, for the time of measurement, pulled against the wall of the measurement vessel by means of the magnetic field. The magnetic particles adhering to the vessel walls are irradiated and the resultant emitted fluorescence is measured.

Abstract: A valve including a valve body having a surface with a plurality of orifices with a resilient closure membrane adjacent thereto is disclosed. The membrane is positioned to yield in response to a pressure differential so as to permit flow between respective ports. A male closure member is mounted to selectively urge the membrane into contact with the periphery of an orifice in order to prevent liquid flow therethrough in accordance with a desired flow arrangement. Further refinements include spring biasing of the closure mechanism, which in one construction has a movable carriage provided with a roller.

Abstract: An apparatus for measuring optical properties such as fluorescence, luminescence or absorption by a liquid sample includes collimating lenses disposed adjacent a cuvette so that their optical axes coincide with the central axis of the cuvette. A fiber bundle with an end portion is located adjacent to the lenses and is provided with a plurality of distinct light transmitting paths extending along the length of the fiber bundle to its end portions. The fiber bundle and collimating lenses cooperate to communicate collimated light between the sample and fiber bundle. The lenses are operable to focus light emanating from the sample upon the end portion of the fiber bundle so that an equal proportion from each volume element of the sample is incident on the fiber bundle surface.

Abstract: Fluorometer in whose reference channel (5) there is optical fiber made of a fluorescent material. The optical fiber acts as an internal standard.

Abstract: Method for the measurement of the difference in the color contents of two samples (1, 2) or of two component areas of a sample, in which method one or several sources of light (3 to 6) as well as one light detector (7) are used. According to the invention, both samples (1, 2), or component areas of a sample, are illuminated simultaneously and, from both samples (1, 2) or component areas of a sample, the light is passed simultaneously to the light detector (7). The lights to be measured from the samples (1, 2) or component areas of a sample are of different colors, as compared with each other, so that the light to be measured from the first sample or component area is absorbed weakly in the coloring agent and the light to be measured from the second sample or component area is absorbed strongly in the coloring agent. The colors of the lights to be measured from the samples (1, 2) or component areas of a sample are alternated with each other at an appropriate frequency, such as, e.g.

Abstract: A photometer with controllable heating plates both above and below the set of sample cuvettes. The photometer is in particular used so that the upper plate is regulated to be warmer.

Abstract: Method for the measurement of the difference in the optical properties dependent on the light direction of two samples (1,2), in which method one or several sources of light (3 to 6) as well as one light detector (7) are used. According to the invention, both of the samples (1, 2) are illuminated simultaneously and from both samples (1, 2) the light is passed simultaneously to the light detector (7). The lights to be measured from the samples (1, 2) have different directions in relation to the sample. The directions of the lights to be measured from the samples (1, 2) are alternated with each other at an appropriate frequency, such as a frequency within the range of 1 c/s to 10,000 c/s. The AC signal given by the light detector (7) is used as a measure of the difference in some optical property dependent on the direction of light between the samples, such as, e.g.

Abstract: A method for detecting and measuring electromagnetic or particle radiation by electrical means has been provided. A piece of semiconductor material, such as phosphorus-doped silicon, fitted with at least two electrodes is used as the detector and the measurement is performed by exposing the detector to the radiation to be measured and by applying an electric field between the electrodes, which will cause an electric breakdown after a certain delay time. The length of this delay time preceding the breakdown is altered by radiation and the magnitude of the change is serving as a measure of the intensity of the radiation falling on the detector.